Enclosed Trailer Questions

Any reason a 1/2 ton truck rated at 12,000#'s towing couldn't handle a 24'? Figure with the trailer weighing 3800, the car at 3200, you're at 7000#'s. So you have quite a bit of room for tools, jacks, etc before you come close to 12,000#'s. With what I take to the track (I also have a 18' open), I sure don't carry anything close to 1000#'s of addtl "stuff." So I figure I'd be at 8000#'s plus or minus tops. To me, that seems well within the capacity of the truck. Curious as I likewise am looking at a 24' enclosed.